Lowri Byrne, who is a size 12, is calling out H&M for its ‘ridiculous’ sizing policy [Photo: Facebook/Lowri Bryne]

A size 12 woman is calling out H&M for its “ridiculous” sizing policy after trying on a size 16 dress that left her feeling like she could “barely breathe.”

Lowri Byrne, an H&M customer in Plymouth, England, expressed her frustration on Facebook Thursday after trying on a blue, strapless dress at the retailer. “Please sort your sizes out because this is absolutely ridiculous!” she wrote in the post that acquired 2,000 comments. “I’m a size 12 and small busted and today in a H&M store I had to ask if this dress came in a size 18 (it didn’t…). The dress I have on in these photos is a size 16, and I could barely breathe. Not only was this annoying because I wanted to buy this dress, but so many women take what size dress they buy to heart. If I was one of these girls (thankfully I’m not) requesting a size 18 dress would seriously devastate me!”

Byrne added that when she asked a salesperson if the dress was available in a size 18, she was told, “Ahh yeah you have to go up a couple of sizes with these.”

In her Facebook post, along with a follow-up post written Monday, Byrne’s followers vented about similar experiences trying to fit into H&M clothing. “I’m not joking when I say that a size 12 dress I bought from H&M fits my 5-year-old daughter! Doesn’t fit me of course,” one mum wrote. Another commented: “I know exactly what you mean — tried on two pairs of size 12 shorts today in H&M — one I could get on without unbuttoning them and the other wouldn’t fasten! It’s crazy!” A third added: “That’s one of the reasons why I stopped shopping at H&M…their sizes are for kids not for women.”

H&M sent the following statement to the Daily Mail on Tuesday: “H&M hugely values all customer feedback. It is only ever our intention to design and make clothes that make our customers feel good about themselves, any other outcome is neither intended nor desired. H&M’s sizes are global and the sizes offered in the UK are the same in all the 66 markets in which we operate in and online. As there is no global mandatory sizing standard, sizes will differ between brands and different markets.”

The statement continued: “Our dedicated, in-house sizing department works according to an average of the sizes and measurements suggested by the markets we operate in. H&M sizes are continually reviewed by our in-house sizing department.”

Neither a representative from H&M UK nor Byrne returned Yahoo Style’s request for comment. However, there has been controversy over sizing policies at other fashion brands, such as American Eagle Outfitters. In May, a woman in Iowa, Riley Bodley, posted a Facebook photo of two pairs of pants purchased from the company, one from five years ago in size 0 and the other a few months before in size 4.

Bummed to have gone up two sizes, Bodley compared the two pants and realised that they were roughly the same size. “This made me wonder, how small has a size 0 actually gotten?” she wrote on Facebook. “The media makes young girls feel the smaller the number they wear, the more beautiful they are, and this is certainly NOT true. I post this as a reminder that size is literally just a number and does not define you. Find clothes that make you feel comfortable and confident, and know your beauty is not defined by the size you wear.”

In 2014, after J.Crew released a new size, 000 — claiming the size was to be sold in Asia and not in America where sizes tend to run larger — customers lashed out at the brand for offering “vanity sizing.”

The practice of vanity sizing involves offering clothing in so-called smaller sizes to appeal to customers’ egos and increase brand loyalty. In other words, if a shopper fits into a surprisingly smaller-than-usual size, she’s more likely to purchase the item and return to the store that makes her feel happier about it.

According to a story in Time, vanity sizing began as a response to the obesity epidemic in the U.S. and as a way to make customers feel optimistic about the shopping experience. The problem, reports the magazine, is that one particular size can vary by as much as several inches.

There’s no evidence that H&M (or any of the aforementioned retailers) participates in vanity sizing. But one thing is clear: the number on the dress tag, just like the number on the scale, is not a measure of anyone’s self-worth.